Compressor wash nozzle integrated in an inlet case strut

ABSTRACT

A compressor wash nozzle integrated in an inlet case strut of a turbine engine is described. A fluid passage and a nozzle are defined in the inlet case strut for delivering a wash/rinse fluid into the inlet gas path of the engine. A fluid connector communicates with the fluid passage and is positioned exteriorly of the inlet gas strut and adapted for receiving pressurized wash/rinse fluid for injection through the nozzle into gases flowing in the inlet gas path and in the direction of the compressor for washing and/or rinsing the blades of the compressor.

TECHNICAL FIELD

The present application relates to a compressor wash nozzle which isintegrated in an inlet case strut of a gas turbine engine.

BACKGROUND ART

During operation of an aircraft turbine engine a significant volume ofair flow through the compressor. Such air, depending on the flight pathwhere the aircraft is operating contains various types of materials suchas dirt, corrosive particulates, dust, salt carried in air when flyingover ocean bodies; etc. This results in deposits on the blades of thecompressor and eventual build-up which has an effect on the performanceof the aircraft engine. Accordingly, the compressor must be washed on aregular basis in order to dislodge these deposits. Typically, turbineengines are cleansed after 200 to 400 hours of operation, depending onthe flight path of the aircraft.

Various devices are known to clean turbine engines by injectingcleansing solution and water into the compressor intake. One such deviceis known as a wash ring which is a complicated tubular array fitted inthe engine and adapted to spray washing and rinsing fluid into thecompressor. This requires installation which is a time-consuming processand adds to the cost of cleansing the compressor. These tubular washrings are also susceptible to damage during handling and storage andtherefore need to be stored in secured areas and inspected fromtime-to-time to make sure that they are in good working condition. Thecleansing process of the compressor is made while the engine is motoredwith the starter but without ignition. After the spraying of cleansingwashing solution and/or water is completed, the igniter is operated inorder to dry the compressor and the combustion chamber.

SUMMARY

According a broad aspect of the application, there is provided acompressor wash nozzle arrangement for a gas turbine engine having aninlet case strut extending through an inlet gas path upstream of acompressor section of the gas turbine engine, the compressor wash nozzlearrangement comprising a fluid passage extending through the inlet casestrut, a nozzle integrated to said inlet case strut and in fluid flowcommunication with said fluid passage and disposed for discharging apressurized wash/rinse fluid into incoming air flowing through the inletgas path, a fluid connector communicating with said fluid passage andpositioned exteriorly of said inlet gas strut and adapted for connectionwith a source of pressurized wash/rinse fluid for injection through saidnozzle into gases flowing though the inlet gas path in the direction ofthe compressor section.

According to a still further broad aspect, there is provided a methodfor cleaning the compressor of a gas turbine engine of the type havingan inlet case strut extending through a inlet gas path upstream of acompressor section of the engine, the method comprising: providing afluid passage in the inlet case strut with a nozzle communicating withthe fluid passage and the inlet gas path, the fluid passage having afluid connector for connecting wash/rinse fluid under pressure to thefluid passage; motoring the gas turbine engine; and injecting, throughthe nozzle, the wash/rinse fluid into the inlet gas path to mix with anincoming flow of air and flow into compressor rotor blades of thecompressor section.

BRIEF DESCRIPTION OF DRAWINGS

Reference is now made to the accompanying figures, in which:

FIG. 1 is a schematic cross sectional view of a turboshaft engine,partly fragmented, to show the location of a compressor wash nozzleintegrated in structural inlet case strut; and

FIG. 2 is a section view through the inlet case strut showing thecompressor wash fluid passage nozzle in relation to the inlet gas pathof the compressor.

DETAILED DESCRIPTION

Referring to the drawings and more specifically to FIG. 1, there isshown a turboshaft gas turbine engine 10 generally comprising acompressor 11 having a compressor rotor 12. An inlet gas path 13 with aradially oriented air intake communicates with the compressor 11 tosupply air thereto. A series of circumferentially distributed solidinlet case struts 14 extend through the inlet gas path 13 upstream ofthe compressor rotor 12. A combustor 15 receives the compressed air andmixes it with fuel which is ignited for generating an annular stream ofhot combustion gases for the turbine section 16.

As will be seen hereinafter, a fluid passage 17 and a wash nozzle 18 areintegrated to at least one of the inlet case struts 14 to inject washingand/or rinsing fluid under pressure into the inlet gas path 13 forwashing the compressor 11 during servicing.

Referring now to FIG. 2, there is shown a section of an inlet case ofthe gas turbine engine 10 through one of the struts 14 of the inletcase. As hereinshown, the fluid passage 17 is machined within the bodyof the inlet case strut 14 and it has a nozzle 18 in communicationtherewith and disposed at a trailing edge of the inlet case strut 14,whereby to minimize the effects of aerodynamics at this trailing edge. Afluid connector 20 is secured to an enlarged inlet end 25 of the fluidpassage 17 and is provided with a coupling 21 for quick connection anddisconnection with a coupling of a fluid hose, not shown, connectablethereto. The fluid connector could also be permanently connected to anairframe mounted tube/hose to which the wash/rinse fluid supply systemconnects.

The coupling 21 is disposed outside of the inlet case on a rear sidethereof so as to be accessible from outside of the gas turbine engine.The hose is, in turn, connected to a pressurized reservoir (not shown)containing a wash/rinse fluid under pressure for injection into thefluid passage 17 and out through the nozzle 18 where a spray of suchwash/rinse fluid is injected into the gas path 13 as represented byspray cone 22. As herein shown the nozzle 18 is oriented to spray thewash/rinse fluid in the direction of the first stage 23 of thecompressor rotor blades 24.

As shown in FIG. 2, the fluid passage 17 as well as the nozzle 18 can bedrilled in the metal strut 14. If the strut 14 is of a hollow strutdesign, then the fluid passage 17 can be integrally cast within thehollow inlet strut. In such case, the coupling 25 and nozzle 18 couldstill be machined for precision reasons.

As can be appreciated, when it is necessary to wash the compressor 11,it is only necessary to attach the wash fluid hose to the fluidconnector 20 provided with the quick coupling 21 at the rear of theinlet case (see FIG. 1). A valve may be provided in the fluid hose tocommunicate the fluid under pressure with the fluid passage 17 after theengine has been motored with the starter and without the ignition. Onthe other hand, if there is no valve in the fluid hose, then it can besecured to the quick coupling 21 after the engine has been motoredwhereby to inject the cleaning wash solution or the water rinse into thefluid passage for spraying into the inlet gas path 13 through the nozzle18. As can be seen, the fluid passage 17 and nozzle 18 do not requirethe addition of material in order to clean the compressor 11 but to thecontrary the method as herein-described is based on material removalfrom the inlet case strut 14, thus reducing weight. The design istherefore lighter as compared to conventional washing techniques such aswash rings or bolt-on nozzles which are secured to the engine. It alsoreduces cost due to handling, storage, maintenance and fabrication.

The above described strut integrated compressor wash nozzle design canbe applied to any turbo shaft, turbo prop or turbo fan engine, eitherwith radial or axial air inlet provided that its compressor is precededby a solid or hollow strut and that it is possible to supply washingfluid to the nozzle through drilled or cast passages.

In summary, the method for cleaning the compressor of a turbine engineof the type having an inlet case strut extending through an inlet gaspath upstream of the compressor, generally comprises providing a fluidpassage in the inlet case strut with a nozzle communicating with thefluid passage and the inlet gas path. The fluid passage has a fluidconnector for connecting wash/rinse fluid under pressure to the fluidpassage. The turbine engine is motored and the wash/rinse fluid isinjected, through the nozzle, into the inlet gas path to mix with theinlet gases and flow into the compressor rotor blades 12.

The integration of a compressor wash nozzle in an inlet case strut of agas turbine engine simplifies the cleansing and/or washing of thecompressor in that it does not require additional fixtures to beconnected to spray wash/rinse fluid under pressure into the compressor.Also it does not require the storage of an additional cleansing unit.

The strut integrated compressor wash nozzle integration permits quickand easy connection of the washing and/or rinsing fluid under pressurefor injection into the compressor.

The above description is meant to be exemplary only, and one skilled inthe art will recognize that changes may be made to the embodimentdescribed therein without departing from the scope of the inventiondisclosed. It is therefore within the ambit of present invention tocover any obvious modifications provided that these modifications fallwithin the scope of the appended claims.

1. A compressor wash nozzle arrangement for a gas turbine engine havingan inlet case strut extending transversally across an inlet gas pathupstream of a compressor section of the gas turbine engine, thecompressor wash nozzle arrangement comprising a fluid passage extendingthrough the inlet case strut, a nozzle integrated to said inlet casestrut and in fluid flow communication with said fluid passage anddisposed for discharging a pressurized wash/rinse fluid into incomingair flowing through the inlet gas path, a fluid connector communicatingwith said fluid passage and positioned exteriorly of said inlet casestrut and adapted for connection with a source of pressurized wash/rinsefluid for injection through said nozzle into gases flowing though theinlet gas path in the direction of the compressor section.
 2. Acompressor wash nozzle arrangement as claimed in claim 1, wherein saidnozzle is provided on a trailing edge of said inlet case strut.
 3. Acompressor wash nozzle arrangement as claimed in claim 2, wherein saidnozzle is a spray nozzle which is oriented to spray said wash/rinsefluid in the direction of a first stage of rotor blades of thecompressor section.
 4. A compressor wash nozzle arrangement as claimedin claim 1, wherein said fluid connector is a hose connector accessiblefrom outside of the gas turbine engine.
 5. A compressor wash nozzlearrangement as claimed in claim 1, wherein said fluid passage is aconduit drilled or cast in the inlet case strut.
 6. A compressor washnozzle arrangement as claimed in claim 5, wherein said nozzle is a drillhole in communication with said fluid conduit.
 7. A gas turbine enginecomprising a compressor wash nozzle arrangement as claimed in claim 1,wherein the gas turbine engine is one of a turbo shaft, turboprop orturbofan engine.